1. Field of the Invention
The invention concerns a device for reclining or seating furniture, wherein the piece of furniture has two or more mutually adjustable, articulated members, which together form an adjustable frame for support of a mattress, cushions, upholstery or the like, where the adjustable frame is mounted in a support member by means of horizontal axles/dowels/stays/sliding elements or the like which constitute pivot points or fulcrums for the mutually adjustable, articulated members, where the back member has a fixed pivot point in relation to the support member, located at a distance from the linkage to the seat member, and that the pivot points for the remaining frame members during adjustment are movable in the length direction of the furniture.
2. Description of the Related Art
In order to obtain different user positions for a piece of reclining or seating furniture, it is usually designed with a frame composed of two or more interlinked parts which form the support for a mattress, cushions, upholstery or the like. The parts of the frame may be incorporated with the mattress, the upholstery etc. or a mattress may be mounted on the frame part, the mattress being designed in such a way that it can follow the frame to the various possible settings. The frame is mounted in a support member which may be mounted in the piece of furniture or form an integrated part of the furniture and it may be in the form of a side member, a gable, a frame or as fixed components. The piece of furniture may be a bed, a chaise lounge, a divan, a bench, a sofa, a chair, etc. In the following description and claims the terms frame, frame member, support member and furniture are intended to cover all such variants.
There are a number of different kinds of reclining and sitting furniture currently on the market equipped with adjustment devices for setting different angles between the back member, the intermediate member or seat member and the foot member in order to provide the article with alternative user positions. The most common examples are adjustable chairs, where the back member and seat member can be set at an angle in relation to each other in order to provide a position of rest or a more active sitting position. Similar solutions have been developed for beds, offering the possibility of assuming a position which is more suitable for reading in bed, etc.
Such adjustment facilities for beds and chairs are employed not only for reasons of comfort, but are particularly important in nursing or illness situations, such as in hospitals or in nursing institutions where the user has to stay for lengthy periods, e.g., in a bed, or in connection with therapeutic chairs for dentists, doctors, etc.
Examples of adjustable reclining or seating furniture can be found in U.S. Pat. No. 4,751,754 and Finnish Pat. No. 89867, both of which disclose adjustable hospital beds, as well as in Danish Pat. Nos. 125771 and 145563, both of which disclose examples of adjustable installation frames for beds. To some extent these previously known constructions have a relatively complicated design. They offer the possibility of different angular adjustments for both the back member, seat member and foot member of the surface of a bed. In designs where the foot member is connected to the seat member and is slidingly guided in the frame of the bed, the foot member will be raised above the surface of the bed in the knee area, which is not always desirable. Alternatively, special joint constructions or additional surface elements have been employed.
In U.S. Pat. No. 4,403,357 a piece of reclining furniture is described, having intermediate elements, each being connected to the adjacent ends of the back member and a leg support member portion by means of pivot joints, which are preferably constructed as elastic pivot joints. Thus the intermediate elements of the under-mattress are connected in a freely suspended manner to the adjacent portions by means of pivot points. The intermediate member permits automatic adjustment of the prevailing sitting position to any desired load conditions. However a motor as an active activator is used in connection therewith.
The object of the present invention is to provide an adjustment device which permits the desired changes in angular adjustment between the seat and the back member, or between the back member, the seat member and the foot member of the frame of an article of furniture. The adjustment device should be simple in design and relatively inexpensive to manufacture, while at the same time it should be possible to perform the angular adjustment either manually or by simple operating means, and preferably with only one single exercise of force.
This object is achieved with an adjustment device of the type mentioned in the introduction, which is characterized by the features presented in the patent claims.
The invention is particularly concerned with a three-part frame for use in a bed or chair, but the invention may also be employed in connection with a two-part construction or a construction with more than three frame members. In every case the back member will be pivotally mounted in a fixed horizontal transverse axis or by means of axis journals some distance above the hinge or link connecting the back member with the seat member. A movement of the back member will result in a movement or rotation of the frame""s other links via the articulations. The description is based on a reclining position where all the parts of the piece of furniture are located in a common, substantially horizontal plane from which position the parts are moved by raising the back member of the frame. In this connection it should be emphasized that in this respect, the description is not intended to be a limiting factor, since the basic position in a chair configuration for a position of rest might just as well be with the back raised, e.g., 60xc2x0. Thus the basis of a reclining position is only used to facilitate the description of the embodiments.
The essential and characteristic feature of the invention is that the rotation of the part of the frame results in a mutual movement of the fulcrum relative to the frame and/or the frame""s support member in the furniture""s longitudinal direction, either in the support member""s plane or along a circular arc based on this plane. This relative movement does not necessarily mean that the fulcrum has to be moved, an alternative being that the frame member may be moved relative to the fulcrum with a similar effect.
In a first embodiment, the seat member is pivotally mounted in a fixed horizontal transverse axis or with axis journals and mounted in a mounting or guide means which permits movement of the transverse axis slidably in an approximately straight line or approximately parallel in relation to the back""s suspension axis. The foot/leg member is pivotally mounted in a movable horizontal transverse axis or by means of axis journals which are mounted on a mounting device which moves the transverse axis slidably in an approximately straight or approximately parallel line. in relation to the back""s and the seat""s suspension axes. In the case of chairs there are not necessarily any foot members. If desired, the chair can be extended with a separate stool or the like.
The lower part of the back, which extends from the mounting axis to the articulation with the seat member can be equipped with a lever which can be influenced by a force, e.g., from a driving mechanism. In order to achieve further adjustment relative to the floor area, according to a further feature of the invention the furniture frame can be combined with a tilting device which can tilt the support frame about a desired smaller angle, e.g., xc2x112xc2x0.
By means of the invention it may be said that adjustable seating furniture is supplied with the advantages which adjustable beds have, and that adjustable beds are provided with the same advantages which exist in adjustable seating furniture. The adjustment device according to the invention offers the possibility of adjusting the angle between the back member and the seat member between 180xc2x0 and 90xc2x0 and between the seat member and a possible foot member between 180xc2x0 and 200-300xc2x0. In addition the angles of the seat member and a possible foot member can be adjusted relative to the floor, even though the back member does not move when the angles deviate from 180xc2x0 and a tilting effect may also be exercised of the order of xc2x112xc2x0. The possibility is thereby obtained of adjusting an angle with the back and the seat member from 180xc2x0, which means that the back and seat members are located on the same plane, to an angular position between the parts. The seat member and the leg member can be angularly adjusted between 180xc2x0 and approximately 100xc2x0 or more. The previously known adjustable beds are normally also hinged or articulated between the individual parts or sections and are usually constructed with heavy, complicated and expensive fittings which by means of manual operation or motor drive will move the various parts into the desired angles. With adjustment devices according to the invention, a simpler, lighter and more reasonably priced adjustment concept is provided in order to satisfy old and new functional requirements in modern times where, amongst other things, people have more leisure. The object is to obtain flexible positions of rest and/or positions which offer the possibility for reading, watching TV or video, surfing on the Internet and the like, thereby reaching new market segments with functional solutions which cover the new requirements for young and old, healthy and handicapped.
As will be illustrated by the following embodiments, the movement of the fulcrums for the seat member and the foot member may be designed in many different ways. The fulcrum, i.e. the mounting point, can be moved by moving a pin on the frame member in grooves provided in the support member or vice versa. The degree of angular adjustment will be dependent on the chosen solution and, particularly in the case of fixed fulcrums where the frame member is moved relative to the fulcrum, it will also be possible to perform an adjustment enabling the beds to be adjusted for other angular variations by means of the same mounting method. If a solution with levers is chosen, the fulcrums for the frame members will be moved along circular paths in the furniture""s longitudinal direction. The choice of solution will depend on the piece of furniture which is to be manufactured and all of these variations are intended to fall within the scope of the invention.